Comments

Let me tell you first off, you're going about it in the right way. Playing with it is a battle. I'm sorry, but 3D Rendering is HARD! It's never easy, no matter how you approach it o what tools you have at your disposal. So, please understand, everyone goes though the kind of frustration you're experiencing.

Secondly, I hope you'll download the materials I put up for the purpose of comparrison. Even if you hate them in your renders, comparing them to what you have now will help you understand what the different parts do.

Jacking down the specular is likely a good idea. I have taken to using specular maps for strength on Ambiance, SubSurface and Specular. Not just any maps, mind you, but high contrast maps like those that come with the Lana character. I use those now almost exclusively on my figures, even if they came from someone else with specular maps included. they're usually not contrasty enough. I have the specular on my characters now dialed down to 25% with a glossiness of 50% or less.

after carefully reading all the replies, this is what i come up with.
the shadow bias really solved the spotlight problem, but the overall look is still not very satisfying to me

i think the essential problem is that Daz Studio still lacks a suitable shader model for human skin or a kind of modular shader thing like the one they had as of poser 9

E.g. if there was a way to specify the sub surface scattering depth, the torchlight problem wouldnt occur. or even a possibility for using dermal and subdermal maps would be great. in a program that focuses on character design, things like that should be a priority ;)

i dislike the way the highlights look, i have seen much better renders and i lack the knowledge to tweak them into something more nice.
also achieving that sexy "wax"-like skin look is very hard.

any ideas?

Ok first off; that "sexy wax" look you're referring to probably is the SSS shader from Poser 2012. You can't get that from Studio as far as I know.

Now for your image what you'll want to do is check if you have a specular map plugged into the spec channel if not the interjection has three different ones. Plug one of them in the Spec colour or the Spec strength channel, this should give you better highlights. If that alone doesn't help, lower the specular strength until you're satisfied with the result.

Furthermore I'd adjust the rimlight so you get just a hair along the edge of the face instead of highlighting a good portion of the side of her head but that's just me...

You can get some pretty amazing effects using this shader but it does take quite a bit of tweaking to get it right.

3Delight is Renderman-complaint, Firefly isn't (I long thought it was, but apparently not - it is however a REYES renderer, which is a larger grouping to which all Renderman-compliant engines belong if I understood correctly).

A huge part of this comes from just tweaking settings. I'm barely starting to scratch the surface on surfaces (bad pun, sorry) but so much of the power comes from playing with 1 setting at a time and just seeing what it does. Switching to the Human Surface Shader or UberSurface (both are included with DAZ) will give you SSS and a lot more control over some other parameters than the basic DAZ shader, plus I find that it just works nicer so I tend to use UberSurface (well UberSurface 2 in my case since I bought it) for just about everything unless I find that switching to it makes things worse and I can't figure out why (had that with 1 surface which heavily relied on the reflection image for its colour and it just changed so much when I switched to US2 and couldn't figure out how to get it back, so I just worked with the basic DAZ shader instead and got it way better).

Now need to start digging into SSS and skin settings in general as that's something I really want to work on so this thread (and its sister African thread) are great.

where do i even choose what shader model is used for a selected surface?!
still tweaking for hours but it doesnt get any better.

a more poser-like sss shader would really be it! especially for the eyes.

Ok, so the thing that's been bothering you is this....

Shadows. I've worked with the interjection shader for a while now and the effect I tend to see is not the effect I'm seeing in your image. Here's why: I'm betting you use UE2 as an ambiant light while l;ighting your model with distant or even spot lights (or a combination) I'm also betting you have UE2 set at 100% intenstity and there's your problem right there. Set UE2 to Ambient Occusion with soft shadows at 20% intenstity and only take it up when the image is too dark.

You could play a little with the colour of your other lights but keep in mind not to over do it; a hint of colour is enough in most cases. Try changing the background colour as well; a portrait against a black background tends to have more impact.

A lot of things have to come together for an image to work don't stare yourself blind on just the surface.

Very interesting thread, specially by the way it begins with lot of beginner's (like I am in realistic rendering) tries out. I have learnt a lot, thanks guys.

I am a DS4 user too, and was worried by the way Poser 2010 performs such great SSS results, much better than DS4, in Renderosity promo pictures.

At this point of doubt, I asked a pair of famous Rendo figures-sellers why their Daz-Studio promo were so poor compared to Poser ones. Their answers converged to something like this:

1.- "The difference comes mainly that our Poser renders are just professional renders and our DS4 renders are not. Have a look in the Rendo forum and see how people obtain disastrous result with SSS in Poser 2010 as well." they said commonly.
2.- Their amazing velvet/Fresnel/reflexion/SSS results are usually obtained with a LOT of ligths, generally around 20-30 lamps of any kind, for a portrait.
3.- They generally generate AO using a separate pre-pass, with untextured models/props and a single GI lighting.
4.- They all said that DS4 has the same specs than Poser, and the different way the engine work is NOT the reason of quality gap, some of them even think that DS is better, but "chuttt ... don't repeat I told you", lol.

Well, I feel challenged, aren't you? (and my best wishes to you for 2013).

Kindly, locusSolus.

PS: @Wancow: Of course I have the Daz Creeper. Is there some different texture for him anywhere? :)

Yes mapped shadows with high bias settings are going to 'miss' a lot of geometry; and for SSS to function properly proper shadowing is a must... raytraced shadows with a little softness and a bias of around 0.1 is a good start.

Regarding the SSS depth thing - this is how far into the substance the light is allowed to pass before it scatters, generally in CM if the shader interface is written correctly. So values around 0.1 are going to be 'correct' for human skin. You'll need to reduce the shading rate for the SSS to around '1' to reduce artifacting. Don't forget to set the index of refraction to 1.3 or so.

I've recently been experimenting with the UberShader2 and had some good results with the SSS engine there.

Check the commentary on this image from my rendo gallery for specifics:

i'm fairly new to DS and try to move over from poser. I successfully converted my V4 character to a Genesis Figure and
now i'm trying to go for the waxy looking realistic skin i was used to from posers latest firefly renderer....

the scene is setup with uberenvironment2 at 50% intensity and a 50% spotlight aswell as a directional light behind the model

but all i could come up with is the attached picture, which gives me a massively glowing head.

any help what i'm doing wrong would be greatly appreciated.

Actually you've done a great job! But there's just a little thing I've seen wrong on this image... The facial skin looks too red, I think it would be better if it'll look naturally. But other than that, it's a great work! http://www.luminoworld.com/

Turn off SSS completely as you don't need it with humans as we're not translucent all the way through, the only SSS you need for 99.999% of your renders is already burned into every realistic texture out there.Subsurface scattering means that light can pass into the object, not necessarily through it all the way. As the name implies, it scatters the light entering the material based on its parameters and reflects the light at the end of its path through the material rather than at the surface where the light beam hit.

Skin is a VERY translucent surface, and no texture regardless of how well made can emulate SSS alone, which is why we have surface shaders. Hold your hand to a bright lamp and you'll see the redness as the light shines through it. Turning off SSS might be suitable for some renders, but for those doing portraits it can add an incredible amount of realism The difference is very noticeable when placed side by side with non SSS surfaces.

Here's a quick comparison. It's Poser, but you can get similar effects in Daz (and better if you use Reality).

No offence to BB, but the one on the left looks more like how my skin looks in the mirror, the one on the right looks out of focus and badly or heavily airbrushed.

I see it looking kind of blurry too, but it is interesting, I think a litte of that blurr-like effect goes a long way. I've been trying to figure out what in the surfaces tab of Daz Studio would make a texture look blurry like that; any ideas?

I see it looking kind of blurry too, but it is interesting, I think a litte of that blurr-like effect goes a long way. I've been trying to figure out what in the surfaces tab of Daz Studio would make a texture look blurry like that; any ideas?

SSS blurs the light (not the materials), and by the way it dissolves sharpness of details and fades out edges of contrasted textures tones.

That is why too high SSS values (strength and depth) turn every figure into an opalescent monochromatic statue.

I had the same issue with Interjection and the glowing face problem. I spent many frustrating hours tweaking HSS shader settings with little or no effect, but then I stumbled across this simple solution through trial and error. I noticed that, for the Subsurface channel, the Subsurface Group is usually 0 (e.g. for V5 Bree, and the Elite textures Nicole and Valerie). Interjection changes the Subsurface Group setting to 5. So, after applying Interjection, I tried various Subsurface Group settings for the face and lip material zones, Settings of 3 or 4 seem to give the best results for the face and lips. I have no idea why this works. I can't find any info on Subsurface Group settings.

Yes mapped shadows with high bias settings are going to 'miss' a lot of geometry; and for SSS to function properly proper shadowing is a must... raytraced shadows with a little softness and a bias of around 0.1 is a good start.

Regarding the SSS depth thing - this is how far into the substance the light is allowed to pass before it scatters, generally in CM if the shader interface is written correctly. So values around 0.1 are going to be 'correct' for human skin. You'll need to reduce the shading rate for the SSS to around '1' to reduce artifacting. Don't forget to set the index of refraction to 1.3 or so.

I've recently been experimenting with the UberShader2 and had some good results with the SSS engine there.

Check the commentary on this image from my rendo gallery for specifics:

Wow, can't believe this is my first post to the "new" forums, been away for a while!

Great info Michael.
Michael. Yes thinking about the measurement increments in Daz Studio 1 being 1CM then a SSS scale of 0.1 makes sense I will have to try that.

The SSS Group setting is for when you have different SSS settings for different parts of the same object. Example I apply SSS to the Sclera, Skin, Teeth etc so I give the Skin a group number say 0 and then Teeth Group 1 and Sclera group 2 and so on. This is so 3Delight knows that different parts have different SSS properties. Without this grouping 3Delight would lump all SSS together as one when calculating.

As for getting a good balance between the colours burnt in to the textures and choosing what colour SSS to have is a matter of trial and error. But starting at a red colour for SSS and adjusting the diffuse has worked for me so far. I found, with using my limited library of older textures that I have in my library, I am choosing a very saturated colour with very little red in for the diffuse colour. ;)

I am just starting to really get some tests going with this and to be honest it a going to take a while to get a grip on what does what and why. To be honest depending on what you want and the look you want there is no right or wrong way to do all this. I don’t use Ambient, I get lights to do that part, some love ambient that is there choice and there make some nice artwork with it too. So who am I to judge or tell anyone what is the right way. But I will say if you want realism then yes I do think there is a more defined path.

This is Chase skin textures by Morris on M4 in DS3A. All rendered with same light set up, Ray Trace Shadow Key Distant light. Two Fill light - Uber Spot two Back Rim lights - Uber Spots, One Bounce - Uber Spot Uber Environment 25% No HDRI Map just using the colour channel set to Occlusion with Soft Shadows. All the spots apart from bounce set to Deep Shadow Maps with 25% soft shadows. All lights white apart from the Uber Environment a mid blue. Oh yes all lights that have shadows, bias set to 0.10

Before: Loaded the skin maps and rendered, granted the lights were set up for the Uber Surfaces mats so it isn't a fair comparison but it does illustrate the change.